1. Field of the Invention
The present invention relates generally to drain pans and, more particularly, to an auxiliary drain pan that is adjustable in size and shape and is structured to minimize pooling of collected liquid, thereby reducing the weight load on the drain pan.
2. Discussion of the Related Art
In various systems and equipment, there is a need to transfer and/or drain liquid to another location. For example, in air conditioning and refrigeration systems, condensation naturally occurs as warm, humid air passes over the exterior of the evaporator coil. Typically, the condensation drips from the evaporator coil into a condensate collection pan positioned below the evaporator coil. From the collection pan, the liquid condensate is directed through a drain line that leads to a safe discharge location, such as the exterior of a building.
Occasionally, problems can occur as a result of a failure in the normal liquid transfer or drainage system. For instance, in an air conditioning system the primary condensate collection pan, usually made of metal materials, is susceptible to rust and corrosion. This can lead to a leak developing in the primary collection pan, causing water damage to the area below the unit. Additionally, mildew and other microbial growths, combined with dust and other particulate, accumulate in the condensate pool. Over time, this accumulation can eventually cause the drain line to become clogged. When this happens, the continually produced condensate fills within the primary condensate collection pan and eventually overflows. The overflow of condensate from a continuously running HVAC unit can cause extensive and costly damage to the interior of a building or home. This is a common problem that is well known in the industry.
To prevent overflow of the primary condensate collection pan, a shut-off switch can be installed. The shut-off switch senses water level in the primary pan and, when the water level reaches a predetermined height, the shut-off switch disables the HVAC system, thereby preventing further condensate accumulation and overflow of the primary pan. A secondary or emergency overflow pan can be installed as an alternative or additional precaution. The secondary pan is installed below the air conditioning unit and is sized, configured and positioned to catch water that might overflow the primary condensate collection pan in the unit. In many cases, the secondary pan is suspended on wires and hangs below the HVAC unit. This emergency overflow pan can also be fitted with a shut-off switch and/or a drain line connection.
While secondary pans are highly effective and can prevent extensive and costly water damage in the event of a primary pan overflow, they too have certain inherent problems and shortcomings. In particular, secondary pans need to be fairly large (i.e., larger than the HVAC unit and primary pan) in order to catch water that may overflow at any area around the base of the HVAC. Accordingly, the secondary or overflow pan provides a large pooling area that, if filled with water, would place a significant weight load on the secondary pan and suspending structure. In order to prevent excess accumulation, or pooling of condensate, the secondary pan needs to be pitched correctly at installation so that water is directed to the drain outlet and into the connected drain line. Unfortunately, the secondary pan is not always installed properly, and the pitch of the pan causes the water to collect away from the drain outlet. And, even if the secondary pan is installed properly, with the correct pitch, the drain outlet or drain line may become clogged as a result of accumulated mildew, dust and other obstructions. In either instance, if the water is not able to freely flow out of the drain outlet through the drain line, condensate will begin to accumulate and pool within the secondary pan. Eventually, the substantial weight load of the accumulated water can cause the secondary pan to buckle, thereby spilling the accumulated water and rendering the secondary drain pan useless.
Accordingly, there remains a need for an improved secondary or auxiliary drain pan that provides a confined area for collection and draining of liquid without excessive pooling of liquid, and thereby reducing the weight load on the drain pan. There is a further need to provide an improved auxiliary drain pan that can be easily adjusted in overall size and shape for customized fitting of the drain pan at the installation site.